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1.
Three CdII coordination polymers (CPs) were synthesized with a tripodal ligand N,N‘,N‘ ‘‐tris(4‐pyridinylmethyl)‐1,3,5‐benzenetricarboxamide in combination with three different substituted isophthalic acids with general formulas {[Cd2( L )(NIP)2(H2O)2].4H2O}n, (CP‐ 1 ), {[Cd2( L )(AIP)2(H2O)2].4H2O}n, (CP‐ 2 ) and {[Cd( L )(BIP) (H2O)].4H2O}n, (CP‐ 3 ). The substituent groups on the co‐ligand had profound effect on the network topologies of the corresponding CPs as well as their properties. Out of the three, CP‐ 1 and 2 were found to form 3D networks whereas CP‐ 3 was a 1D linear chain with uncoordinated pyridyl sites. Due to its structural features CP‐ 3 was found to show interesting properties. The 1D CP containing uncoordinated pyridyl site exhibited an excellent ability for doping with CoII which in turn acts as an efficient water oxidation electrocatalyst with required overpotential of 380 mV for an anodic current density of 1 mA cm?2. The CP also exhibited luminescence‐based detection of nitroaromatics (LOD: 0.003 mm ) without any significant interference in presence of other organic compounds.  相似文献   

2.
The title compound, [Mg2(C12H14O4)2]n, is the first example of an s‐block metal adamantanedicarboxylate coordination polymer. The asymmetric unit comprises two crystallographically unique MgII centers and two adamantane‐1,3‐dicarboxylate ligands. The compound is constructed from a combination of chains of corner‐sharing magnesium‐centered polyhedra, parallel to the a axis, connected by organic linkers to form a layered polymer. The two MgII centers are present in distorted tetrahedral and octahedral coordination environments derived from carboxylate O atoms. Tetrahedrally coordinated MgII centers have been reported in organometallic compounds, but this is the first time that such coordination has been observed in a magnesium‐based coordination polymer. The bond valance sums of the two MgII centers are 2.05 and 2.11 valence units, matching well with the expected value of 2.  相似文献   

3.
A single crystal to single crystal transmetallation process takes place in the three‐dimensional (3D) metal–organic framework (MOF) of formula MgII2{MgII4[CuII2(Me3mpba)2]3}?45 H2O ( 1 ; Me3mpba4?=N,N′‐2,4,6‐trimethyl‐1,3‐phenylenebis(oxamate)). After complete replacement of the MgII ions within the coordination network and those hosted in the channels by either CoII or NiII ions, 1 is transmetallated to yield two novel MOFs of formulae Co2II{CoII4[CuII2(Me3mpba)2]3}?56 H2O ( 2 ) and Ni2II{NiII4[CuII2(Me3mpba)2]3}? 54 H2O ( 3 ). This unique postsynthetic metal substitution affords materials with higher structural stability leading to enhanced gas sorption and magnetic properties.  相似文献   

4.
Two new ZnII coordination polymers (CPs), [Zn2(SA)2(L)2]n ( 1 ) and [Zn(AA)(L)]n ( 2 ) [L = 1,6‐bis(benzimidazol‐1‐yl)hexane, H2SA = succinic acid, H2AA = adipic acid], were synthesized via hydrothermal method and characterized by elemental analysis, infrared spectroscopy, and single‐crystal X‐ray diffraction. CP 1 possesses a sql network, which is further extended into a 3D supramolecular skeleton by non‐classical C–H ··· O hydrogen bonding interactions. CP 2 exhibits a 1D linear chain, which is further assembled into a 2D supramolecular layer by π ··· π stacking interactions. The solid state fluorescence properties of two ZnII CPs were investigated. Both CPs present high photocatalytic activities for the degradation of methylene blue (MB) under UV light irradiation. The photodegradation efficiency using CP 1 as catalyst is 91.3 % and using CP 2 as catalyst is 85.0 %, respectively.  相似文献   

5.
The preparation, crystal structures, and thermal properties of [Ca(pyr)2(4‐nba)2]n ( 1 ) (pyr = pyrazole; 4‐nba = 4‐nitrobenzoate) {[Ca(H2O)2(3‐npth)] · H2O}n ( 2 ) (3‐npth = 3‐nitrophthalate), [Mg(H2O)5(3‐npth)] · 2H2O ( 3 ), and [Mg(H2O)4(2‐nba)2] ( 4 ) (2‐nba = 2‐nitrobenzoate) are reported. The anhydrous CaII compound 1 and the diaqua CaII‐3‐nitrophthalate monohydrate 2 are one‐dimensional coordination polymers containing a hexacoordinate CaII ion located on a center of inversion in 1 and a heptacoordinated CaII ion in 2 . In 1 , the 4‐nitrobenzoate moiety acts as a μ2‐bridging bidentate ligand, whereas the 3‐nitrophthalate anion exhibits a μ3‐bridging pentadentate coordination mode in 2 . The hexacoordinate MgII‐containing compounds 3 and 4 do not contain a [Mg(H2O)6]2+ unit and the central MgII ion is coordinated to at least one monodentate carboxylate unit namely the monodentate 3‐npth molecule in 3 and two trans monodentate 2‐nba molecules in 4 . Hydrogen bonding between the lattice water molecules results in the formation of a water dimer in 3 . A comparative study of 17 alkaline earth nitrocarboxylates is described.  相似文献   

6.
The imidazole‐based dicarboxylate ligand 2‐(4‐(pyridin‐4‐yl)phenyl)‐1H‐imidazole‐4,5‐dicarboxylic acid (H3PyPhIDC), was synthesized and its coordination chemistry was studied. Solvothermal reactions of CaII, MnII, CoII, and NiII ions with H3PyPhIDC produced four coordination polymers, [Ca(μ3‐HPyPhIDC)(H2O)2]n ( 1 ), {[M32‐H2PyPhIDC)23‐HPyPhIDC)26(H2O)2] · 6H2O}n [M = Mn ( 2 ), Co ( 3 )], and {[Ni(μ3‐HPyPhIDC)(H2O)] · H2O}n ( 4 ). Compounds 1 – 4 were analyzed by IR spectroscopy, elemental analyses, and single‐crystal and powder X‐ray diffraction. Compound 1 displays a one‐dimensional (1D) infinite chain. Compounds 2 and 3 are of similar structure, showing 2D network structures with a (4,4) topology based on trinuclear clusters. Compound 4 has another type of 2D network structure with a 3‐connected (4.82) topology. The results revealed that the structural diversity is attributed to the coordination numbers and geometries of metal ions as well as the coordination modes and conformations of H3PyPhIDC. Moreover, the thermogravimetric analyses of all the compounds as well as luminescence properties of the H3PyPhIDC ligand and compound 1 were also studied.  相似文献   

7.
The CoII atom in bis(5‐aminotetrazole‐1‐acetato)tetraaquacobalt(II), [Co(C3H4N5O2)2(H2O)4], (I), is octahedrally coordinated by six O atoms from two 5‐aminotetrazole‐1‐acetate (atza) ligands and four water molecules. The molecule has a crystallographic centre of symmetry located at the CoII atom. The molecules of (I) are interlinked by hydrogen‐bond interactions, forming a two‐dimensional supramolecular network structure in the ac plane. The CdII atom in catena‐poly[[cadmium(II)]‐bis(μ‐5‐aminotetrazole‐1‐acetato], [Cd(C3H4N5O2)2]n, (II), lies on a twofold axis and is coordinated by two N atoms and four O atoms from four atza ligands to form a distorted octahedral coordination environment. The CdII centres are connected through tridentate atza bridging ligands to form a two‐dimensional layered structure extending along the ab plane, which is further linked into a three‐dimensional structure through hydrogen‐bond interactions.  相似文献   

8.
The use of pyridine‐2,4‐dicarboxylic acid (H2pydc) in the construction of SrII and SrII‐MII (M=Co, Ni, Zn and Cu) coordination polymers is reported. Eight complexes, that is, [Sr(pydc)H2O]n ( 1 ), [MSr(pydc)2(H2O)2]n (M=Co ( 2 ), Ni ( 3 ), Zn ( 4 )), [ZnSr(pydc)2(H2O)7]n?4 nH2O ( 5 ), [SrCu(pydc)2]n ( 6 ), [SrCu(pydc)2(H2O)3]n?2 nH2O ( 7 ), and [Cu3Sr2(pydc)4(Hpydc)2(H2O)2]n ( 8 ), have been synthesized via dexterously choosing the appropriate strontium sources and transition metal salts, and rationally controlling the temperature of the reaction systems. Complexes 1 , 2 ( 3 , 4 ), 6 , and 8 display four types of 3‐D framework structures. Complexes 5 and 7 exhibit a 2‐D network and a 1‐D chain structure, respectively. The 2‐D complex 7 can be reversibly transformed into 3‐D compound 6 through temperature‐induced solvent‐mediated structural transformation. The luminescent property studies indicated that complex 1 shows a strong purple luminescent emission and 4 exhibits a strong violet luminescence emission. The magnetic properties of 2 , 3 , and 8 were also studied. Antiferromagnetic MII???MII interactions were determined for these complexes.  相似文献   

9.
In the title compound, [Cu(C14H18O4)(H2O)]n, each CuII atom bonds to four O atoms of four adamantanediacetate (ada) ligands in equatorial positions and an O atom from a water mol­ecule in the apical position. Two adjacent CuII atoms form a paddle‐wheel unit with four ada ligands. The distance between the two Cu atoms is 2.5977 (3) Å. A crystallographic inversion center is located at the center of the Cu–Cu core. Each Cu2(ada)4 paddle‐wheel further bonds to four adjacent identical paddle‐wheel units, generating a two‐dimensional layered structure of Cu(ada)(H2O) with a 44 topology.  相似文献   

10.
A new coordination polymer (CP), namely, poly[[diaquatris[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene]bis[μ6‐4‐(2,4‐dicarboxylatophenoxy)phthalato]tetracobalt(II)] hexahydrate], {[Co4(C16H6O9)2(C12H10N4)3(H2O)2]·6H2O}n, has been synthesized by solvothermal reaction. The CP was fully characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single‐crystal X‐ray diffraction. It presents a three‐dimensional (3D) structure based on tetranuclear CoII secondary building units (SBUs) with a tfz‐d net and point symbol (43)2(46·618·84). The 4‐(2,4‐dicarboxyphenoxy)phthalic acid (H4dcppa) ligands are completely deprotonated and link {Co4(COO)4}4? SBUs into two‐dimensional (2D) layers. Furthermore, adjacent layers are connected by 1,4‐bis(1H‐imidazol‐1‐yl)benzene (bib) ligands, giving rise to a 3D supramolecular architecture. Interestingly, there are numerous elliptical cavities in the CP where isolated unique discrete hexameric water clusters have been observed. The results of thermogravimetric and magnetic analyses are described in detail.  相似文献   

11.
The title compound, [Cu2(SO4)2(C10H8N2)2(C2H6O2)2(H2O)2]n, contains two crystallographically unique CuII centres, each lying on a twofold axis and having a slightly distorted octahedral environment. One CuII centre is coordinated by two bridging 4,4′‐bipyridine (4,4′‐bipy) ligands, two sulfate anions and two aqua ligands. The second is surrounded by two 4,4′‐bipy N atoms and four O atoms, two from bridging sulfate anions and two from ethane‐1,2‐diol ligands. The sulfate anion bridges adjacent CuII centres, leading to the formation of linear ...Cu1–Cu2–Cu1–Cu2... chains. Adjacent chains are further bridged by 4,4′‐bipy ligands, which are also located on the twofold axis, resulting in a two‐dimensional layered polymer. In the crystal structure, extensive O—H...O hydrogen‐bonding interactions between water molecules, ethane‐1,2‐diol molecules and sulfate anions lead to the formation of a three‐dimensional supramolecular network structure.  相似文献   

12.
In the title compound, {[Co(C14H8N2O5)(C10H8N2)]·3H2O}n, the CoII cation is five‐coordinated with a slightly distorted trigonal–bipyramidal geometry, and the 5‐isonicotinamidoisophthalate ligands link CoII atoms into a layered structure. These two‐dimensional arrays are further pillared by rod‐like 4,4′‐bipyridine ligands to give a three‐dimensional framework with pcu (primitive cubic) topology. The magnetic and adsorption properties of the title compound are also discussed.  相似文献   

13.
The heterometallic CuII‐BaII coordination polymer, namely [CuBa(tdc)2(H2O)(DMF)]n ( 1 ) (H2tdc = 2,5‐thiophenedicarboxylic acid, DMF = N,N′‐dimethylformamide), was solvothermally synthesized by the reaction of H2tdc, CuCl2 · 2H2O, and Ba(NO3)2. Single crystal X‐ray diffraction analysis reveals that compound 1 features a 3D intricate framework with the 1D channels occupied by the coordinated solvent molecules. After removing the coordinated solvent molecules, the desolvated samples of 1a exhibit high capacity for light hydrocarbons.  相似文献   

14.
A 2D-to-2D (2D: two-dimensional) structural transformation accompanying significant bond rearrangement and coordination environment change is demonstrated in a coordination polymer (CP) comprised of copper(II) ions and terephthalate (BDC2−) ligands for the first time. When immersed in water, a free-standing membrane of 2D Cu(BDC)(DMF) ( Cu-1 ; DMF: N,N-dimethylformamide) transforms into 2D Cu(BDC)(H2O)2 ( Cu-2 ) while maintaining its highly oriented layered structure. In the 2D sheet, paddlewheel-type CuII dimers coordinated with four bidentate BDC ligands in a square-planar array in Cu-1 were released to form uniform aqua-bridged CuII chains, which are cross-linked with each other by unidentate BDC ligands, in Cu-2 . The present facile approach to implement the 2D-to-2D transformation accompanied by bond rearrangement, which is characteristic of CPs, leads to a marked increase in in-plane magnetic susceptibility and proton conductivity. In situ experiments in support of theoretical calculations unveiled the energy diagram that governs the unique structural transformation.  相似文献   

15.
Three coordination compounds with dimensions from 0D to 2D, namely, [Co(bppdca)2(HL1)2] ( 1 ) [Co(bppdca)(L2)(H2O)] · 2H2O ( 2 ) and [Co(bppdca)(L3)] · 3H2O ( 3 ) [bppdca = N,N′‐bis(pyridine‐3‐yl)pyridine‐2,6‐dicarboxamide, H2L1 = 2,5‐pyridinedicarboxylic acid, H2L2 = 4,4′‐oxybisbenzoic acid, H2L3 = 2‐carboxymethylsulfanyl nicotinic acid] were hydrothermally synthesized and structurally characterized. Single crystal X‐ray diffraction analysis reveals that complex 1 is a discrete 0D complex, in which the bppdca ligand and the H2L1 act as the terminal groups to coordinate with the CoII ions. In coordination polymer 2 , two bppdca ligands coordinate in anti configuration with two CoII ions to generate a 28‐membered Co2(bppdca)2 loop, which is further extended into 1D ladder‐like double chain by pairs of L2 ligands. In 3 , the CoII ions are linked by bppdca ligands to generate 1D wave‐like chain, which is further connected by the L3 to form a 2D network. Finally, the coordination compounds 1 – 3 are extended into 3D supramolecular frameworks through the hydrogen bonding interactions. The CoII ions and the bppdca ligands in the title coordination compounds exhibit different coordination characters and conformations. The effect of organic dicarboxylates with different rigidity and length on the structures of CoII coordination compounds was investigated. In addition, the fluorescence and electrochemical behaviors of coordination compounds 1 – 3 were reported.  相似文献   

16.
The title complex, [MnII(nic)2(H2O)2]n [nic is 3‐pyridine­carboxyl­ate (also called nicotinate), C6H4NO2?], has a two‐dimensional layer structure with the unique Mn atom on an inversion centre. In each layer, all nicotinate ligands are coordinated to Mn atoms in a bridging/bidentate mode, thus linking the {MnII(nic)2(H2O)2} monomeric units together to form a dative‐bond‐based layered polymer. The intra‐layer hydrogen bonds involving all water mol­ecules and the carboxyl­ate groups may play an auxiliary part in stabilizing the layer. The layers are arranged in an ordered manner along the a axis through van der Waals forces so as to complete the solid‐state structure of the crystal.  相似文献   

17.
Coordination polymers constructed from metal ions and organic ligands have attracted considerable attention owing to their diverse structural topologies and potential applications. Ligands containing carboxylate groups are among the most extensively studied because of their versatile coordination modes. Reactions of benzene‐1,4‐dicarboxylic acid (H2BDC) and pyridine (py) with ZnII or CoII yielded two new coordination polymers, namely, poly[(μ4‐benzene‐1,4‐dicarboxylato‐κ4O:O′:O′′:O′′′)(pyridine‐κN)zinc(II)], [Zn(C8H4O2)(C5H5N)]n, (I), and catena‐poly[aqua(μ3‐benzene‐1,4‐dicarboxylato‐κ3O:O′:O′′)bis(pyridine‐κN)cobalt(II)], [Co(C8H4O2)(C5H5N)2(H2O)]n, (II). In compound (I), the ZnII cation is five‐coordinated by four carboxylate O atoms from four BDC2− ligands and one pyridine N atom in a distorted square‐pyramidal coordination geometry. Four carboxylate groups bridge two ZnII ions to form centrosymmetric paddle‐wheel‐like Zn22‐COO)4 units, which are linked by the benzene rings of the BDC2− ligands to generate a two‐dimensional layered structure. The two‐dimensional layer is extended into a three‐dimensional supramolecular structure with the help of π–π stacking interactions between the aromatic rings. Compound (II) has a one‐dimensional double‐chain structure based on Co22‐COO)2 units. The CoII cations are bridged by BDC2− ligands and are octahedrally coordinated by three carboxylate O atoms from three BDC2− ligands, one water O atom and two pyridine N atoms. Interchain O—H…O hydrogen‐bonding interactions link these chains to form a three‐dimensional supramolecular architecture.  相似文献   

18.
The layered CuII coordination polymer {[Cu(tib)2(H2O)2](NO3)2} ( 1 ) based on the rigid tripodal 1,3,5‐tris(1‐imidazolyl)benzene (tib) ligand was synthesized by hydrothermal methods. By introducing different polycarboxylate coligands from linear 4,4′‐biphthalic acid (H4L1) to V‐shaped thiophene‐2,5‐dicarboxylic acid (H2L2), two new copper(II) compounds were obtained, namely, {Cu(tib)(H2L1)(H2O) · 3H2O} ( 2 ) and {Cu(tib)(L2) · 3H2O} ( 3 ). X‐ray diffraction analyses reveal that compound 2 displays a hydrogen‐bonded three‐dimensional (3D) supramolecular structure, in which protonated {H2L1}2– ligands occupy some coordination sites around the metal atoms to form one‐dimensional (1D) chain by blocking the formation of two‐dimensional (2D) Cu‐tib layer as in compound 1 . Interestingly, compound 3 features a rare twofold interpenetrating binodal seh ‐3,5‐P43212 topological network by synergistic effect of V‐shaped carboxylate group and functionally complementary N‐donor ligand. These compounds were characterized by elemental analyses, thermogravinetric analyses, and photoluminescent spectroscopy.  相似文献   

19.
The title complex, {[Cd(C8H11O4)2(C10H8N2)(H2O)]·H2O}n, consists of linear chains formed through 4,4′‐bipyridine ligands linking seven‐coordinated CdII ions. Each CdII ion is in a distorted penta­gonal–bipyramidal environment, coordinated by one water ligand, two 4‐carboxy­cyclo­hexane‐1‐carboxyl­ate ligands and one bridging 4,4′‐bipyridine ligand to generate linear chains. The water mol­ecules and the Cd atom on one side, and the 4,4′‐bipyridine unit on the other, are bisected by two sets of twofold axes. The carboxylate group of the 4‐carboxy­cyclo­hexane‐1‐carboxyl ligand chelates a CdII ion, while the (protonated) carboxyl group forms hydrogen bonds with adjacent chains, resulting in a layered structure. This is the first reported occurrence of a dicarboxycyclo­hexane ligand exhibiting a non‐bridging coordination mode.  相似文献   

20.
A ZnII complex of a C2‐chiral bisamidine‐type sp2N bidentate ligand ( L R ) possessing two dioxolane rings at both ends catalyzes a highly efficient quinone asymmetric Diels‐Alder reaction (qADA) between o‐alkoxy‐p‐benzoquinones and 1‐alkoxy‐1,3‐butadienes to construct highly functionalized chiral cis‐decalins, proceeding in up to a >99:1 enantiomer ratio with a high generality in the presence of H2O (H2O:ZnII=4–6:1). In the absence of water, little reaction occurs. The loading amount of the chiral ligand can be minimized to 0.02 mol % with a higher Zn/ L R ratio. This first success is ascribed to a supramolecular 3D arrangement of substrates, in which two protons of an “H2O‐ZnII” reactive species make a linear hydrogen bond network with a dioxolane oxygen atom and one‐point‐binding diene; the ZnII atom captures the electron‐accepting two‐points‐binding quinone fixed on the other dioxolane oxygen atom via an n‐π* attractive interaction. The mechanisms has been supported by 1H NMR study, kinetics, X‐ray crystallographic analyses of the related Zn L R complexes, and ligand and substrate structure‐reactivity‐selectivity relationship.  相似文献   

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